Support watching of individual files.

lib/fssm.rb

@@ -12,15 +12,7 @@ def dbg(msg=nil)
 
     def monitor(*args, &block)
       monitor = FSSM::Monitor.new
-      context = args.empty? ? monitor : monitor.path(*args)
-
-      if block_given?
-        if block.arity == 1
-          block.call(context)
-        else
-          context.instance_eval(&block)
-        end
-      end
+      FSSM::Support.use_block(args.empty? ? monitor : monitor.path(*args), block)
 
       monitor.run
     end
@@ -33,7 +25,8 @@ def monitor(*args, &block)
 require 'fssm/support'
 require 'fssm/tree'
 require 'fssm/path'
-require 'fssm/state'
+require 'fssm/state/directory'
+require 'fssm/state/file'
 require 'fssm/monitor'
 
 require "fssm/backends/#{FSSM::Support.backend.downcase}"

lib/fssm/backends/fsevents.rb

@@ -7,18 +7,17 @@ def initialize
       @fsevents = []
     end
 
-    def add_path(path, preload=true)
-      handler = FSSM::State.new(path)
-      @handlers["#{path}"] = handler
+    def add_handler(handler, preload=true)
+      @handlers[handler.path.to_s] = handler
 
-      fsevent = Rucola::FSEvents.new("#{path}", {:latency => 0.5}) do |events|
+      fsevent = Rucola::FSEvents.new(handler.path.to_s, {:latency => 0.5}) do |events|
         events.each do |event|
           handler.refresh(event.path)
         end
       end
 
       fsevent.create_stream
-      handler.refresh(path.to_pathname, true) if preload
+      handler.refresh(nil, true) if preload
       fsevent.start
       @fsevents << fsevent
     end

lib/fssm/backends/inotify.rb

@@ -4,14 +4,12 @@ def initialize
       @notifier = INotify::Notifier.new
     end
 
-    def add_path(path, preload=true)
-      handler = FSSM::State.new(path)
-
-      @notifier.watch(path.to_s, :all_events) do |event|
+    def add_handler(path, preload=true)
+      @notifier.watch(handler.path.to_s, :all_events) do |event|
         handler.refresh(event.name)
       end
 
-      handler.refresh(path.to_pathname, true) if preload
+      handler.refresh(nil, true) if preload
     end
 
     def run

lib/fssm/backends/polling.rb

@@ -5,9 +5,8 @@ def initialize(options={})
       @latency = options[:latency] || 1.5
     end
 
-    def add_path(path, preload=true)
-      handler = FSSM::State.new(path)
-      handler.refresh(path.to_pathname, true) if preload
+    def add_handler(handler, preload=true)
+      handler.refresh(nil, true) if preload
       @handlers << handler
     end
 

lib/fssm/monitor.rb

@@ -6,16 +6,17 @@ def initialize(options={})
 
   def path(*args, &block)
     path = FSSM::Path.new(*args)
+    FSSM::Support.use_block(path, block)
 
-    if block_given?
-      if block.arity == 1
-        block.call(path)
-      else
-        path.instance_eval(&block)
-      end
-    end
+    @backend.add_handler(FSSM::State::Directory.new(path))
+    path
+  end
+
+  def file(*args, &block)
+    path = FSSM::Path.new(*args)
+    FSSM::Support.use_block(path, block)
 
-    @backend.add_path(path)
+    @backend.add_handler(FSSM::State::File.new(path))
     path
   end
 

lib/fssm/state/directory.rb

@@ -0,0 +1,57 @@
+module FSSM::State
+  class Directory
+    attr_reader :path
+
+    def initialize(path)
+      @path = path
+      @cache = FSSM::Tree::Cache.new
+    end
+
+    def refresh(base=nil, skip_callbacks=false)
+      previous, current = recache(base || @path.to_pathname)
+
+      unless skip_callbacks
+        deleted(previous, current)
+        created(previous, current)
+        modified(previous, current)
+      end
+    end
+
+    private
+
+    def created(previous, current)
+      (current.keys - previous.keys).each {|created| @path.create(created)}
+    end
+
+    def deleted(previous, current)
+      (previous.keys - current.keys).each {|deleted| @path.delete(deleted)}
+    end
+
+    def modified(previous, current)
+      (current.keys & previous.keys).each do |file|
+        @path.update(file) if (current[file] <=> previous[file]) != 0
+      end
+    end
+
+    def recache(base)
+      base = FSSM::Pathname.for(base)
+      previous = @cache.files
+      snapshot(base)
+      current = @cache.files
+      [previous, current]
+    end
+
+    def snapshot(base)
+      base = FSSM::Pathname.for(base)
+      @cache.unset(base)
+      @path.glob.each {|glob| add_glob(base, glob)}
+    end
+
+    def add_glob(base, glob)
+      FSSM::Pathname.glob(base.join(glob).to_s).each do |fn|
+        @cache.set(fn)
+      end
+    end
+
+  end
+end

lib/fssm/state/file.rb

@@ -0,0 +1,24 @@
+module FSSM::State
+  class File
+    attr_reader :path
+
+    def initialize(path)
+      @path = path
+    end
+
+    def refresh(base=nil, skip_callbacks=false)
+      base ||= @path.to_pathname
+      used_to_exist, @exists = @exists, base.exists?
+      # this handles bad symlinks without failing. why handle bad symlinks at
+      # all? well, we could still be interested in their creation and deletion.
+      old_mtime, @mtime = @mtime, base.symlink? ? Time.at(0) : base.mtime if @exists
+
+      unless skip_callbacks
+        @path.delete(@path.to_s) if used_to_exist && !@exists
+        @path.create(@path.to_s) if !used_to_exist && @exists
+        @path.update(@path.to_s) if used_to_exist && @exists && old_mtime != @mtime
+      end
+    end
+
+  end
+end

lib/fssm/support.rb

@@ -48,5 +48,14 @@ def rb_inotify?
       end
     end
 
+    def use_block(context, block)
+      return if block.nil?
+      if block.arity == 1
+        block.call(context)
+      else
+        context.instance_eval(&block)
+      end
+    end
+
   end
 end